Primality proof for n = 56767:

Take b = 2.

b^(n-1) mod n = 1.

9461 is prime.
b^((n-1)/9461)-1 mod n = 63, which is a unit, inverse 42350.

(9461) divides n-1.

(9461)^2 > n.

n is prime by Pocklington's theorem.